1. The Field of the Invention
The present invention relates to a remote safety switch for use in operating machinery. More specifically, the present invention relates to a safety switch which provides greater safety in situations where two or more persons are working together in operating a machine by providing each operator a switch, such as a foot switch, which works in combination with the other operator's switch or switches to control the machinery. The safety switch allows for the operation of a machine which does not have a similar type of safety switch with the safety switch of the present invention.
2. State of the Art
Switches, such as foot switches are used to control pieces of machinery. A foot switch may be used to turn the machine on or off or activate one of the machine's functions. The foot switch typically turns the machine on or operates a particular function of the machine when stepped on or otherwise depressed, and causes the machine to cease operation when released.
Many machines do not have such foot switches or safety switches. Additionally, if a foot switch is available, it may not provide adequate safety in operating a machine or adequate control over the machine. Existing foot switches work in some situations where a single person operates a piece of machinery. Existing foot switches do not, however, work well with some types of machinery, or where two or more persons operate a single piece of machinery. In such a situation, only one person may stop the machinery if an undesired event or emergency occurs. In many situations, noise, lack of visual contact, or the like inhibit communication between operators and may create a dangerous situation. Where only one operator is in control of the machinery, that operator may be without knowledge of the other operator, and thus unable to stop the machine if a problem develops related to the other operator. If one operator notices a problem but does not have control over the machinery, they may be unable to quickly stop the machinery or communicate the problem to the other operator.
It is not uncommon to have multiple persons operating a piece of machinery. Multiple persons may be required to feed large pieces of material into a machine such as a saw or press. In such situations, the operators may often be in relatively close proximity. If an operator without control over the machinery notices a problem, they may be unable to quickly stop the machine or communicate the problem to the other operator so as to prevent damage or injury. Noise or other obstacles may inhibit communication between the operators.
In other situations, the operators may not be in close proximity, and may not be in visual contact. An example of this type of situation is where electricians are pulling wire through conduit for an electrical installation. Commonly, the wire is fed into the conduit in one location and pulled from the conduit in another location which may be in another room or another floor of a building.
While telephones or radios may be used to communicate, noise may prevent such communication, or the task being performed may prevent a person from using telephone or radio. Even if communication is possible, a person in control of the machine may simply not react quickly enough when a problem is communicated to them by the other machine operator so as to avoid an accident. It will be appreciated that where an operator communicates the existence of a problem over radio, telephone, or the like to another machine operator having a safety switch such as a foot switch, several seconds may pass before the operator having the foot switch realizes what is happening and stops the machine. The passage of several additional seconds may result in damage to the machine, improper execution of the task, or even injury to the machine operator.
There is thus a need for a device which allows multiple operators to each have control over a piece of machinery. There is need for a device which allows any of multiple operators to shut down a piece of machinery quickly if necessary. There is also need for a device which facilitates communication between multiple machine operators such that the machine may safely and properly be operated in an environment where noise or other impediments prevents communication between the machine operators.